In brewing, an infection refers to significant levels of any microbes in the beer wort other than the desired yeast. Potential infecting microbes include wild yeasts (and other fungi), as well as various bacteria. Symptoms of an infection can vary widely depending on the specific infecting microbe(s), and can include (but are not limited to): mold growing in the fermenter, strange odors and/or flavors, overcarbonated bottles, rings of scum in the bottles, and clumps or strands of gelatinous material.